During May 2025, Andrey Monakov contributed to the rust-lang/gcc repository by addressing a targeted bug in GCC’s tree-cfg.cc, refining the handling of CONJ_EXPR to enforce its use exclusively with COMPLEX_TYPE. This change improved type safety and reduced the risk of incorrect abstract syntax tree construction. Andrey also refactored error handling logic, consolidating it for better readability and maintainability. Working primarily in C++, he applied expertise in compiler development, code refactoring, and type systems to enhance the reliability of type checks. The work demonstrated a deep understanding of GCC internals and contributed to smoother future development in the codebase.